As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI N1 FLUCUATES BETWEEN 24.4-26.7 BOTH ENGINES AT IDLE. AIRCRAFT BACK TO BLOCK AND GROUNDED BY MAINTENANCE. MAINTENANCE RAN ENGINES TO T/O PWR IAW B767 AMM 71-00-00 N 1 FLUCTUATIONS WITHIN LIMITS WITH EEC'S INOP NO SURGE NOTED. AIRCRAFT RETURNED TO SERVICE.